The protracted pre-trial mud-slinging match between Heather Mills McCartney and her estranged husband Sir Paul McCartney today entered a new phase in its hostility. While Sir Paul has sought to keep a low profile ahead of divorce proceedings, Ms Mills has been subjected to a mauling at the hands of the media. He reportedly locked her out of the house and quizzed her personal trainer over their relationship, while she stood accused of various past misdemeanours. This case was getting ugly but it had not yet got too personal.

Today, however, the first four pages of a Daily Mail splash were headlined: "Heather: Macca 'beat me up'."

Today's accusations of violence and drunken behaviour on the part of Sir Paul may swing the public perception PR pendulum back in Ms Mills's favour.

These are serious allegations, but are they credible?

We are told they derive from some 13 pages of the divorce documents filed by Ms Mills. So they are not only serious but also, it is alleged, contained in a legal document forming the basis of the pending proceedings. To the extent that they may be contained in legal documentation, do they have to be true?

While the media busily speculates, Ms Mills's lawyers, Mischon de Reya, are not commenting on the leaked documents. They have, however, been reported as saying that their client stands by everything that has been filed at court and intends to provide proof at trial if necessary. Yet this does not confirm that what has been filed at court is what has been spread across the newspapers.

This leads to an interesting conundrum as to whether we are dealing with a leaked legal document that is potentially privileged or a publicity stunt that seeks to undermine the public perception of one of the parties to the proceedings.

If these are the real court documents and it has been leaked, that is itself a cause for concern both to the parties and the court. Whatever the impact on the public, it will be the courts and not the people who decide what is just, if the case finally reaches a courtroom. As a civil family case, it will be a judge who makes the final ruling, so the risk of media-infused jury bias is not present.

However, if an eventual court ruling were not as sympathetic to Ms Mills as the public might expect, could the publication of this leaked document undermine such a ruling and run the risk of contempt?

Possibly, but that is if the case makes it to court. This raises the next question: are these pleadings playing to an audience in a bid to force a lucrative out of court settlement?

Lawyers have expressed fears that amendments to the civil procedure rules allowing disclosure of documents filed in advance of cases being heard in court could lead to media savvy litigants putting PR into their pleadings. However, in this case we are dealing with leaked documents that have not been confirmed.

Whether true or fake, the effect of the document is one of defamation by divorce proceedings.

Whether true or fake, Sir Paul's outrage at its publication can be countered with the cloak of privilege or public interest that may allow the Daily Mail and others to get away with such seemingly sensational coverage.

· Edgar Forbes is senior lecturer in media law at The Media School, Bournemouth University

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